Endocrine Abstracts

Introduction

Myxedema coma is a rare condition with an estimated incidence of 0.22 per million per year in the western world and a mortality rate around 30–50%. It can occur as the result of severe longstanding hypothyroidism or be precipitated by an acute event, such as infection. We present a rare case of myxedema coma in an elderly woman with SARS-CoV-2 infection.

Case report

An 82-year-old woman, with no previous history of hypothyroidism, presented with signs of breathing difficulty for the past 2 days associated with progressive lethargy and constipation. She had history of arterial hypertension, dyslipidaemia, and chronic kidney disease (KDIGO 4 stage). She had a uterine neoplasm discovered in contrasted CT scan but refused to undergo further studying. Her chronic medication included simvastatin, clopidogrel, furosemide, irbesartan and hydrochlorothiazide. In the physical examination, she was pale and dehydrated. Glasgow coma scale (GCS): 9 points. Blood pressure was 84/56 mmHg, heart rate of 60 bpm, temperature 36.2ºC and peripheral oxygen saturation of 94% at room air. Cardiopulmonary auscultation was normal. Her abdomen was diffusely tender to palpation and she had no peripheral oedema. Her initial blood work showed anaemia (10.3 g/dl), hyponatremia (126 mmol/l), hyperkalemia (5.7 mmol/l) and acute kidney injury (creatinine 1.67 mg/dl and urea 113 mg/dl). SARS-CoV-2 PCR testing was positive. Chest roentgenogram demonstrated signs of bilateral pneumonia. Head CT showed no recent vascular events. She was admitted and started fluid resuscitation with 0.9% saline. On the second day of hospitalization, she became unresponsive (GCS: 3 points) and presented oxygen desaturation, needing supplemental oxygen therapy with FiO2 80%. She was hypotensive (90/56 mmHg), bradycardic (45 bpm), and hypothermic (32.4ºC). She showed signs of inadequate perfusion of extremities, with barely palpable peripheral pulses. Her blood work evidenced pancytopenia, elevated transaminases, hyponatremia (132 mmol/l), hyperkalemia (5.3 mmol/l), PCR 24.5 mg/dl, procalcitonin 0.22 ng/ml, free T4 <0.25 ng/ml and TSH 52.67 µU/ml. She was diagnosed with myxedema coma triggered by SARS-CoV2 infection and treated with 200 mg hydrocortisone and 200 µg l-thyroxine intravenously. Despite these measures, she showed no signs of response and died within a few hours.

Discussion

Myxedema coma diagnosis requires a high level of clinical suspicion. This is the second described case of myxedema coma in a COVID-19 patient. In this patient, factors favouring this diagnosis were the coma status, hypoventilation, hypotension, bradycardia, hyponatremia and hypothermia. The SARS-CoV2 infection, a virus with known neurological tropism, might have impaired the ventilatory response even more.